proteoglycan

https://doi.org/10.1351/goldbook.P04899
A subclass of protein in which the carbohydrate units are polysaccharides that contain amino sugars. The protein is glycosylated by one or more (up to about 100) glycosaminoglycans [linear polymers of up to about 200 repeating disaccharide units that consist of a hexosamine (d-glucosamine or d-galactosamine) alternating with a uronic acid (d-glucuronic or l-iduronic) or a neutral sugar (d-galactose)].
Sources:
PAC, 1988, 60, 1389. 'Nomenclature of glycoproteins, glycopeptides and peptidoglycans (Recommendations 1985)' on page 1391 (https://doi.org/10.1351/pac198860091389)
White Book, 2nd ed., p. 85 (https://www.qmul.ac.uk/sbcs/iupac/bibliog/white.html)